Video Game History Timeline - The Strong National Museum of Play
John Madden Football (1990) - MobyGames
The History of Football Games - GameSpot
John Madden Dead: NFL Coach, Longtime Broadcaster & Video Game Pioneer Was 85 – Deadline
Madden 23 review: Filler clutters an otherwise improved game - The Washington Post
Video games then and now: What 11 popular video games looked like when they first came out and today
History of the Madden Cover Athlete
John Madden Football (PC, 1988) - Video Game Years History
John Madden Football for the Apple II